caches.py

# -*- coding: utf-8 -*-
# Copyright (c) 2015 Jason Power
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# Authors: Jason Power

""" Caches with options for a simple gem5 configuration script

This file contains L1 I/D and L2 caches to be used in the simple
gem5 configuration script. It uses the SimpleOpts wrapper to set up command
line options from each individual class.
"""
import m5
from m5.objects import Cache

# Add the common scripts to our path
m5.util.addToPath('../../')

from common import SimpleOpts

# Some specific options for caches
# For all options see src/mem/cache/BaseCache.py

class L1Cache(Cache):
    """Simple L1 Cache with default values"""

    assoc = 2
    tag_latency = 2
    data_latency = 2
    response_latency = 2
    mshrs = 4
    tgts_per_mshr = 20

    def __init__(self, options=None):
        super(L1Cache, self).__init__()
        pass

    def connectBus(self, bus):
        """Connect this cache to a memory-side bus"""
        self.mem_side = bus.slave

    def connectCPU(self, cpu):
        """Connect this cache's port to a CPU-side port
           This must be defined in a subclass"""
        raise NotImplementedError

class L1ICache(L1Cache):
    """Simple L1 instruction cache with default values"""

    # Set the default size
    size = '16kB'

    SimpleOpts.add_option('--l1i_size',
                          help="L1 instruction cache size. Default: %s" % size)

    def __init__(self, opts=None):
        super(L1ICache, self).__init__(opts)
        if not opts or not opts.l1i_size:
            return
        self.size = opts.l1i_size

    def connectCPU(self, cpu):
        """Connect this cache's port to a CPU icache port"""
        self.cpu_side = cpu.icache_port

class L1DCache(L1Cache):
    """Simple L1 data cache with default values"""

    # Set the default size
    size = '64kB'

    SimpleOpts.add_option('--l1d_size',
                          help="L1 data cache size. Default: %s" % size)

    def __init__(self, opts=None):
        super(L1DCache, self).__init__(opts)
        if not opts or not opts.l1d_size:
            return
        self.size = opts.l1d_size

    def connectCPU(self, cpu):
        """Connect this cache's port to a CPU dcache port"""
        self.cpu_side = cpu.dcache_port

class L2Cache(Cache):
    """Simple L2 Cache with default values"""

    # Default parameters
    size = '256kB'
    assoc = 8
    tag_latency = 20
    data_latency = 20
    response_latency = 20
    mshrs = 20
    tgts_per_mshr = 12

    SimpleOpts.add_option('--l2_size', help="L2 cache size. Default: %s" % size)

    def __init__(self, opts=None):
        super(L2Cache, self).__init__()
        if not opts or not opts.l2_size:
            return
        self.size = opts.l2_size

    def connectCPUSideBus(self, bus):
        self.cpu_side = bus.master

    def connectMemSideBus(self, bus):
        self.mem_side = bus.slave